Edible Film Developers

[grainyvision]

So, it's not quite what I'd call edible (well, you wouldn't want to put more than a drop on tongue at a time for sure) but I've recently found the primary component of cinnamon essential oil (cinnaldehyde) may (more like.. a very small chance) have some use in replacing the traditional formaldehyde as a sulfite-pump. This sulfite-pump behavior is super useful in lith developers to keep the hydroquinone alive without having too much sulfite that will react with the resulting quinone radicals responsible for "infectious development". The paper I found that hints at this behavior is here: https://www.researchgate.net/public...ores_of_the_enal_and_enone_types_with_sulfite

Anyone more knowledgeable in chemistry than me in this thread care to tell me if it's an absolute not possible or a maybe?

 

[tezzasmall]

Phew!!! I find it hard to believe that I've just read the majority of the posts over the last two days, and skimmed a little of it. A lot to take in.

But apart from not letting this thread die after such a lot of input, it has made me more curious and makes me want to try out a few ideas mentioned, but as asked for by a few, to try and get an 'edible' print developer concoction to work...

Terry S

 

[tezzasmall]

Being the last poster so far, I thought that I would add the following. Also note that there is a newer conversation about this subject at this link:

https://www.photrio.com/forum/threads/herb-developer.188968/

Since my last post on this thread, (I meant to report back) I tried various things recommended as well as things not(!) trying to find a herbal paper developer.

I tried fresh and dried rosemary quite a lot, in various amounts. With a brew of rosemary only I managed to get a mid grey on the paper = about 5/10. Adding vitamin C and sodium carbonate, I got a much darker tone at about 9/10, although this was a test with white light. Using the enlarger and LONG negative exposures, produced little or only very slight tones on the paper. Having just read the comments previous to mine, a test would have to be done of the last two ingredients alone as well, which I didn't do.

I also tried actual cloves along with clove and other various essential oils alone and then mixed with polysorbate 20, a 'solubiliser', which helps the oils mix into the liquid better. All of this was to little or no effect though.

Finally, I tried human urine, at various strengths, as it was also recommended, again with and without the vitamin C and sodium carbonate. No tone in the paper was forthcoming and the stronger strengths are definitely NOT recommended in a small darkroom without good ventilation!!!

Terry S

 

[AgX]

With a brew of rosemary only I managed to get a mid grey on the paper = about 5/10. Adding vitamin C and sodium carbonate, I got a much darker tone at about 9/10, although this was a test with white light. Using the enlarger and LONG negative exposures, produced little or only very slight tones on the paper.

The in effect spectral dependability of this developer is most interesting, and should be further investigated on.

 

[faberryman]

I haven't read all 500+ posts, but is anybody doing the chemistry or is this just a random walk through the spice cabinet and...er...well...uh...the toilet? To the extent any of these experiments work, do they improve the image quality over traditional developers? I checked out the price of spices when I was at the grocery store yesterday, and I think it is safe to say that developing film with spices is not going to be a cost savings measure.

 

[AgX]

"What do you mean by "doing the chemistry" ?
Going through the spice cabinet is a very practical approach.

If you mean reasearching plants on their content of developing agents? Not having been done to my knowledge. But there has been done research on the content of Antioxidants, part of which are reducing agents. Which again might act as developing agent.

But in both cases any such figures do not mean much, as such agents, if contained at all, must be practically be extractable, and remaining active after this, by our very own means.

Thus the practical approach above does not seem bad to me.

 

[Alan Johnson]

https://nutritionj.biomedcentral.com/articles/10.1186/1475-2891-9-3
The antioxidant content is in the various full size tables but it probably does not predict activity.

 

[Raghu Kuvempunagar]

Edible film developers are mostly bogus. But there is an edible salt that works well as toner for both film and paper:

https://www.photrio.com/forum/threads/kala-namak-sepia-toner-for-indirect-toning.189469/

https://www.photrio.com/forum/threads/toning-b-w-slides-with-kala-namak.189593/

https://www.photrio.com/forum/threa...t-makes-a-terrific-toner.148338/#post-1941999

 

[Alan Johnson]

I agree with most of what Raghu writes on this topic, particularly if experimenters don't check if most of the Development is being done by Ascorbate Alone.
But here is one [Amla] which does work but it gives a very low EI and takes hours to work at 25C:
https://www.photrio.com/forum/threads/edible-film-developers.33501/page-13#post-1776371
Some of them will work along with phenidone ,which helps them to part up with electrons.
Some do work with ascorbate, the edible substance is adsorbed on silver grains and passes electrons from the ascorbate, maybe.
Of course, ascorbate and phenidone obviously cannot be included in the same mix.

 

[Raghu Kuvempunagar]

Amla is supposed to be a good natural source of Vitamin C. It could be the Vitamin C in Amla that makes it a weak developer. And if Phenidone is added to such a developer, activity is likely to increase.

 

[tezzasmall]

I'm (really) sure that a table was linked to a post on this thread near the beginning(ish), but don't remember where. It was a list of LOADS of various items and then there was a percentage of something that helped development and in another column saying how much. I think that was why rosemary and cloves were mentioned by various people, as these two had the most by far. If no one else manages to find it, I'll have another look when I've got more time... hint, hint.

Terry S

 

[faberryman]

"What do you mean by "doing the chemistry"? Going through the spice cabinet is a very practical approach.

What I mean by doing the chemistry is answering the question if rosemary works as a developer, why does it work? What properties does rosemary have that causes it to develop film? And then answering the question what other spices or foods have the same properties? That would seem to be the scientific approach, rather than just randomly picking spices off the spice rack, or randomly picking vegetables out of the vegetable drawer, or randomly opening a can of whatever off the shelf in the cupboard.

 

[AgX]

Well, the content of "free phenols" in vegetables has been established in research as hinted at above.

One may guess that these or some of these have developing-agent character as the snythetic made phenol-derivates we use so far. In these studies the chemical structures of these phenols are not given as far as I know.

 

[Donald Qualls]

if rosemary works as a developer, why does it work?

We don't even know what the developing agent is in coffee, and that's actually been studied, some.

 

[Alan Johnson]

Amla is supposed to be a good natural source of Vitamin C. It could be the Vitamin C in Amla that makes it a weak developer.

If you exclude food or herbs that contain vitamin C you exclude virtually the whole lot:
https://www.news-medical.net/health/Sources-of-Vitamin-C.aspx
However your main point that the effect of added ascorbic acid should be tested for is IMO entirely valid.
Your point seems to be that even if this test is passed it does not prove that polyphenols in foods/herbs are the main developing agent.

 

[Donald Qualls]

Polyphenols from other sources are known to act as developing agents. There are a number of plant-based substances (at the least, coffee will without adding ascorbate -- and I'm fairly sure there's no significant level of ascorbate in actual coffee). Caffeic acid has been shown not to be responsible. What else would you suggest that's a component of coffee that develops film in sufficiently alkaline conditions? Presumably not catechols (else drinking coffee wouldn't be safe). That points pretty strongly toward polyphenols.

 

[Alan Johnson]

My bit of evidence that Polyphenols can be the main developing agent in edible foods is also based on coffee.
It was shown that that caffeic acid [not photo grade] could develop film:
https://www.photrio.com/forum/threads/caffeic-acid-fill-of-beans.115988/
[The thread also discusses what else might contribute to coffee development]
Caffeic acid is a Polyphenol, as discussed here:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6734135/

 

[AgX]

Interesting in this article for us not that deep into biochemistry is this table with phenolic acids, to give an idea what we are talking about:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6734135/bin/gr1.jpg

 

[Alan Johnson]

I remembered that some time ago I made an experiment using Broccoli +phenidone.
Broccoli contains about 90mg ascorbic acid per 100g and it appeared then that this content of ascorbic acid in the food is about the level in the food at which the ascorbate starts to do a significant proportion of the development. Below that I assume the development is mainly the result of what is loosely termed polyphenol but I was not too sure about it.
https://www.photrio.com/forum/threads/developer-from-broccoli.83138/page-2#post-1124945

 

[Donald Qualls]

I wanted to post the Caffenol recipe I used before I started adding ascorbate. Here it is:

8 oz. Water
2 tsp (level) Arm & Hammer Washing Soda
4 tsp (slightly rounded) Folger's Coffee Crystals

Mix soda until completely dissolved and solution is clear. Add coffee, mix until all grittiness is gone and solution is uniform, let stand 5-10 minutes until microbubbles clear. Use within 30 minutes. Gives imagewise stain and general (fog) stain.

This works equally well with any "crystals" type instant coffee (after initial tests, the next time I bought coffee for this (I don't drink instant unless it's an emergency) I bought the cheapest they had at the supermarket that looked like Folger's Crystals. I gave 30 minutes at 20C for both the Tri-X that was fresh in 2003, and for Fomapan 100 (9x12 sheets).

Later, I learned about adding ascorbate:

8 oz. Water
2 1/2 tsp (level) Arm & Hammer Washing Soda
1 g Ascorbic acid or erythorbic acid (supplement or technical, 97%)
4 tsp (slightly rounded) Folger's Coffee Crystals

Mix as for Caffenol. Expect slight film speed increase (1/3 to 2/3 stop) and little or no stain.

The increase in alkali is to offset the acidity of the ascorbic acid; it's unnecessary if you use sodium ascorbate. I gave this only 12 minutes, but got more fog than with the original, and less imagewise stain.

Where I found coffee really shines is on microfilm stocks; I created Caffenol L(ow)C(ontrast)+C in 2005.

Caffenol LC+C (speed enhancing low contrast microfilm developer)

8 oz Water
4 tsp (level) Arm & Hammer Washing Soda
.26 g (4 grain) Ascorbic acid or erythorbic acid (supplement or technical, 97%)
2 tsp (slightly rounded) Folger's Coffee Crystals

Use with microfilms to give increased speed with pictorial contrast. No detectable stain.

If you're not equipped to measure sub-gram amounts of ascorbic acid, you can mix 1/4 tsp in a quart of water and use 8 ounces of that to mix the developer. I gave this 15 minutes at 20C, agitating only every 3rd minute; I got EI 50-64 with Copex Rapid and EI 20 with original Adox CMS 20, but with good dynamic range and pictorial tonality (but still with the extreme fine grain and sharpness characteristic of those stocks). MUCH cheaper than H&W Control, though about 1/3 stop lower film speed.

 

[AgX]

I wonder what Momme Andresen would say about this thread.

 

[RalphLambrecht]

It would be fun to put together a whole list of processing 'chemicals' exclusive made of organic and house hold supplies.

 

[Raghu Kuvempunagar]

I remembered that some time ago I made an experiment using Broccoli +phenidone.
Broccoli contains about 90mg ascorbic acid per 100g and it appeared then that this content of ascorbic acid in the food is about the level in the food at which the ascorbate starts to do a significant proportion of the development. Below that I assume the development is mainly the result of what is loosely termed polyphenol but I was not too sure about it.
https://www.photrio.com/forum/threads/developer-from-broccoli.83138/page-2#post-1124945

Fruits, vegetables and herbs that are rich in Ascorbic acid might do weak development of film in alkaline solutions of appropriate pH due to fact that Ascorbic acid is a developing agent. However, if they need additional Ascorbic acid and/or Phenidone for proper development of film, I think it defeats the purpose.

If polyphenols do really contribute to developing activity, then one should be able to show that a fruit/vegetable/herb that is rich in both polyphenols and Ascorbic acid can do normal development of film by itself in an appropriate alkaline environment. Or at least, one should be able to show substantially more development than what is possible with equivalent amount of Ascorbic acid. After all, it is claimed by many here that these polyphenols are super-additive with Ascorbic acid.

 

[Raghu Kuvempunagar]

I wanted to post the Caffenol recipe I used before I started adding ascorbate. Here it is:

8 oz. Water
2 tsp (level) Arm & Hammer Washing Soda
4 tsp (slightly rounded) Folger's Coffee Crystals

Do you have any examples of film negatives developed with this formula that you can share?

 

[Donald Qualls]

I have scans from when I was using a 1998 scanner at 1200 ppi.

Spotmatic SP, Super Takumar 50/1.4, early 2000s Tri-X, Caffenol (no ascorbate). Here's a crop:

Grain is "crisp". Scanner doesn't do much with the imagewise stain, though that would show in darkroom prints on multicontrast as a softening of grain, as well as smoothing of mid-tones due to the color of the stain.

Here's another one, with Fomapan:

Kawee Camera (aka Patent Etui, 13.5 cm f/4.5 Radionar), 9x12 cm Fomapan 100, Caffenol (no ascorbate).